1. Field of the Invention
The present invention relates to the field of playing card shufflers and particularly to the use of a gravity feed system for assisting entry of the cards into a transportation system or card moving system of a playing card shuffling system.
2. Background of the Art
In the gaming industry, certain games require that batches of randomly shuffled cards be provided to players and sometimes to dealers in live card games. It is important that the cards are shuffled thoroughly and randomly to prevent players from having an advantage by knowing the position of specific cards or groups of cards in the final mass of cards delivered in the play of the game. At the same time, it is advantageous to have the deck(s) shuffled in a very short period of time so that there is minimal down time in the play of the game.
U.S. Pat. No. 5,944,310 describes a card handling apparatus comprising: a loading station for receiving cards to be shuffled; a chamber to receive a main stack of cards; delivery means for delivering individual cards from the loading station to the chamber; a dispensing station to dispense individual cards for a card game; transfer means for transferring a lower most card from the main stack to the dispensing station; and a dispensing sensor for sensing one of the presence and absence of a card in the dispensing station. The dispensing sensor is coupled to the transfer means to cause a transfer of a card to the dispensing station when an absence of a card in the dispensing station is sensed by the dispensing sensor. Individual cards delivered from the loading station are randomly inserted by insertion means into different randomly selected positions in the main stack to obtain a randomly shuffled main stack from which cards are individually dispensed. The insertion means includes vertically adjustable gripping means to separate the main stack into two spaced substacks to enable insertion of a card between the substacks by the insertion means. The gripping means is positionable vertically along the edges of the main stack. After gripping, the top portion of the stack is lifted, forming two sub-stacks. At this time, a gap is created between the stacks.
Similarly, U.S. Pat. No. 5,683,085 describes apparatus for shuffling or handling cards including a chamber in which a main stack of cards are supported, a loading station for holding a secondary stack of cards, and card separating mechanism for separating cards at a series of positions along the main stack to allow the introduction of cards from the secondary stack into the main stack at those positions. The separating mechanism grips cards at the series of positions along the stack and lifts those cards at and above the separation mechanism to define spaces in the main stack for introduction of cards from the secondary stack.
U.S. Pat. No. 5,676,372 describes an automated playing card shuffler, comprising: a frame; an unshuffled stack holder for holding an unshuffled stack of playing cards; a shuffled stack receiver for holding a shuffled stack of playing cards; at least one ejector carriage mounted adjacent to said unshuffled stack holder, said at least one ejector carriage and said unshuffled stack holder mounted to provide relative movement between said unshuffled stack holder and said at least one ejector carriage; a plurality of ejectors mounted upon said at least one ejector carriage adjacent the unshuffled stack holder, for ejecting playing cards from the unshuffled stack, said ejecting occurring at various random positions along the unshuffled stack.
U.S. Pat. Nos. 6,139,014 and 6,068,258 describe a machine for shuffling multiple decks of playing cards in a batch process. The device includes a first vertically extending magazine for holding a stack of unshuffled playing cards, and second and third vertically extending magazines each for holding a stack of cards, the second and third magazines being horizontally spaced from and adjacent to the first magazine. A first card mover is positioned at the top of the first magazine for moving cards from the top of the stack of cards in the first magazine to the second and third magazines to cut the stack of unshuffled playing cards into two unshuffled stacks. Second and third card movers are at the top of the second and third magazines, respectively, for randomly moving cards from the top of the stack of cards in the second and third magazines, respectively, back to the first magazine, thereby interleaving the cards to form a vertically registered stack of shuffled cards in the first magazine. Elevators are provided in the magazines to bring the cards into contact with the card movers.
U.S. Pat. No. 6,019,368 describes a playing card shuffler having an unshuffled stack holder that holds an infeed array of playing cards. One or more ejectors are mounted adjacent the unshuffled stack holder to eject cards from the infeed array at various random positions. Multiple ejectors are preferably mounted on a movable carriage. Extractors are advantageously used to assist in removing playing cards from the infeed array. Removal resistors are used to provide counteracting forces resisting displacement of cards, to thereby provide more selective ejection of cards from the infeed array. The automated playing card shuffler comprises a frame; an unshuffled stack holder for holding an unshuffled array of playing cards in a stacked configuration with adjacent cards in physical contact with each other and forming an unshuffled stack; a shuffled array receiver for holding a shuffled array of playing cards; at least one ejector for ejecting playing cards located at different positions within the unshuffled stack; and a drive which is controllable to achieve a plurality of different relative positions between the unshuffled stack holder and said at least one ejector.
U.S. Pat. No. 6,149,154 describes an apparatus for moving playing cards from a first group of cards into plural groups, each of said plural groups containing a random arrangement of cards, said apparatus comprising: a card receiver for receiving the first group of unshuffled cards; a single stack of card-receiving compartments generally adjacent to the card receiver, said stack generally adjacent to and movable with respect to the first group of cards; and a drive mechanism that moves the stack by means of translation relative to the first group of unshuffled cards; a card-moving mechanism between the card receiver and the stack; and a processing unit that controls the card-moving mechanism and the drive mechanism so that a selected quantity of cards is moved into a selected number of compartments.
U.S. Pat. No. 6,254,096 describes an apparatus for continuously shuffling playing cards, said apparatus comprising: a card receiver for receiving a first group of cards; a single stack of card-receiving compartments generally adjacent to the card receiver, said stack generally vertically movable, wherein the compartments translate substantially vertically, and means for moving the stack; a card-moving mechanism between the card receiver and the stack; a processing unit that controls the card-moving mechanism and the means for moving the stack so that cards placed in the card receiver are moved into selected compartments; a second card receiver for receiving cards from the compartments; and a second card-moving mechanism between the compartments and the second card receiver for moving cards from the compartments to the second card receiver.
U.S. Pat. No. 6,267,248 describes an apparatus for arranging playing cards in a desired order, said apparatus including: a housing; a sensor to sense playing cards prior to arranging; a feeder for feeding said playing cards sequentially past the sensor; a storage assembly having a plurality of storage locations in which playing cards may be arranged in groups in a desired order, wherein the storage assembly is adapted for movement in at least two directions during shuffling; a selectively programmable computer coupled to said sensor and to said storage assembly to assemble in said storage assembly groups of playing cards in a desired order; a delivery mechanism for selectively delivering playing cards located in selected storage locations of the storage assembly; and a collector for collecting arranged groups of playing cards.
U.S. Pat. No. 4,586,712 describes a card shuffling apparatus that comprises an input apparatus, an output storage means and an interposed shuffling storage means. The cards are inserted via a narrow gap into the shuffling storage means. Sensors (photoelectric cells) check whether the respective compartments of the shuffling storage means are free for receiving cards, with the status of each compartment being stored in an electronic register.
EP 0 777 514 B1 describes a card shuffling apparatus that conveys the cards from an input apparatus to a shuffling storage means and from there to the output storage means. The introduction into the shuffling storage means occurs via guide elements which press the currently drawn card against draw-in rollers. Sensors detect whether cards are conveyed out of the input apparatus into the shuffling container and from there out again in order to enable the control of the respective motors for driving the draw-in rollers and the shuffling storage means.
U.S. Pat. No. 6,889,979 suggests that the teachings in the art of playing card shufflers relates to technical solutions for shuffling playing cards and that little emphasis is placed on a continual verification of the number of used playing cards situated in the card shuffler. That patent asserts that this disadvantage is avoided by providing a card shuffler which is capable of displaying continuously the number of playing cards situated in the card shuffler or in the shuffling storage means and to thus giving the operator the opportunity to have certainty at all times about the complete number of playing cards. The described shuffling system offers an error-free possibility of detecting the number of the cards situated in the shuffling storage means, thus reducing the possibility of unauthorized and unnoticed removal of cards from a game. The introduction of a card into the shuffling storage means and the removal of the cards from the shuffling storage means can be detected in a contact free manner.
There are essentially four or five types of automatic playing card shuffler formats known in the art, and those formats include 1) a riffling or interleaving action in which cards are separated into approximately two stacks of cards and shuffled together (riffled) to combine the two sets into a single set, 2) a system wherein two stacks of cards are provided with a central stack of cards, and cards are randomly moved from the top of the two stacks into a central stack (and some of the cards from the central stack may also be moved randomly back into the two stacks) until a final single stack of cards is formed, 3) a single set of cards is moved one card at a time randomly into compartments (carousels, fans, wheel, stacks, etc.) and the cards in the compartments are delivered to a final card collection area, and 4) a set of cards has cards randomly ejected from within the set and transported to a collection area (or compartments and then a collection area). These shuffler systems are taught in the above cited references, all of which are herein incorporated in their entireties by reference.
In feeding a single deck or a single set of cards into shufflers where a single deck or single set of cards is initially provided, and cards are removed from the single deck or single set, one-at-a-time from the single set to another function in the shuffler, a number of problems tend to arise. Among the more common problems are the ability to consistently feed a single card (rather than multiple cards) from the single set into the shuffler, the ability to assure that the last of the playing cards in the first set placed into the input area are moved out of the system, and preventing premature activation of the removal of cards by the shuffler as the first set of playing cards are inserted into the input area.